The National Cancer Institute (NCI) has proposed creating a multi- institutional Cooperative Breast Cancer Tissue Registry (CBCTR) as a means of procuring and distributing archived paraffin embedded breast cancer tissues from patients with a known clinical outcome to support investigators validating potential prognostic and therapeutic markers. More than 250 new breast cancers are diagnosed each year among the ethnically diverse population of American blacks. Hispanics and non- Hispanic whites served by the University of Miami/Jackson Memorial Hospital; approximately 4,000 breast cancer patients are currently registered in our clinical data base. This proposal describes the personnel, patient clinical data and tissue resources available to the CBCTR the categories of tissues to be registered, the means of selecting, storing and retrieving pertinent tissues, the coordination of clinical data and tissues, the appropriate preparation of tissues for distribution to investigators and the quality mechanisms necessary to achieve the goals of the Registry. The medicolegal aspects of the use of excess tissue for research are also addressed. The University of Miami/Jackson Memorial Hospital is an excellent site for a branch of this NCI-sponsored Cooperative Registry and pledges full cooperation to achieve its goals.